1. Field of the Invention
The present invention relates to an electronic device such as a transmission/reception unit of a cellular phone, a television tuner or the like.
2. Description of Related Art
In a conventional electronic device illustrated in FIG. 7, in a transmission/reception unit of a cellular phone, a cover 11 is used for shielding various electric components mounted on a circuit board.
As shown in FIG. 7, the cover 11 is formed with one metal plate, and has an upper wall 12, a side wall 13 bent downward from the four sides of the upper wall 12, and plural rectangular holes 14 formed on the border between the upper wall 12 and the side wall 13.
Upon formation of the cover 11, first, the plural rectangular holes 14 are formed in four side portions of the flat metal plate so as to facilitate bending.
Next, the four sides of the upper wall 12 are bent at a right angle with respect to one side edge of each hole 14, to form the side wall 13. Thus the cover 11 is completed.
Further, if the cover 11 that covers the electric components is used in an electronic device, as the holes 14 are open, the electric shielding is degraded.
In the conventional electronic device, having the holes 14 on the border between the upper wall 12 and the side wall 13 of the cover 11, as the holes 14 are open, electric shielding is poor.
The present invention provides, as one means of solving the above problem, an electronic device comprising a case body having a box shape, comprising a metal plate, constituting a frame or a cover, wherein the case body has a side wall bent with respect to a hole provided in a flat plate, and wherein the side wall has an extruded portion to cover the hole.
Further, the present invention provides, as another means of solving the problem, the electronic device having the above construction, wherein the extruded portion, with an edge portion of the hole, extends toward an inner surface side of the flat plate, so as to cover the hole.
Further, the present invention provides, as another means of solving the problem, the electronic device having the above construction, wherein the extruded portion is formed by an extrusion process or drawing process.
Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same name or similar parts throughout the figures thereof.